Outboard motor mount for depth regulation



July 26, 1955 A. J. PLO'UFF 2,713,842

OUTBOARD MOTOR MOUNT FOR DEPTH REGULATION Filed Oct. 8, 1952 2o z 20 J2 United States Patent O OUTBOARD MOTOR MOUNT FOR DEPTH REGULATION Arthur J. Ploulf, Escanaba, Mich. Application October 8, H52, Serial No. 313,646 11 Claims. (Cl. 115-41) My invention relates to an improved mount for outboard motors and more specifically to a mount for attaching an outboard motor to the stern of a boat so that the depth of submersion of the propeller of the motor is variable and this depth may be readily and easily adjusted.

When operating a boat propelled by an outboard motor in lakes or streams with shallow, rocky bottoms or with stumps and snags lying close to the surface of the water, the operator must be constantly alert to see that the propeller is not so deep as to run into the rocks or snags and thereby be damaged. The usual way of making draft adjustments for these dangerous shoal areas involves tipping the motor up on its mounting brackets by bearing down on the motor handle. The pivot itself is stiff and the balance of the motor is such as to oppose this movement. This pivoting action in outboard motors in my experience is always very stiff. A third factor which contributes still further to the difficulty of the tilting is the thrust of the propeller which acts counter to the movement.

The gross difiiculty resulting from these several factors means that the tipping can usually be accomplished only by the operator changing his position from the normal and comfortable driving position which is always inconvenient and sometimes dangerous. At best, the difficulty itself is ever present. Operation over lengthy shoal areas introduces the further difiiculty, not only of tilting the motor, but of holding the motor tilted.

A further objection to tilting the motor, of a very different nature, is that the motor operates inefficiently when the propeller axis is tilted at more or less of an angle to the surface of the water.

Quite aside from avoiding the difficulties presented by rocky bottoms, stumps and snags in shallow waters when propelling a boat by an outboard motor, is the ever present problem of moving the propeller away from the lake or stream bottom when bringing the boat ashore. Commonly a boat propelled by an outboard motor is driven up on a shelving bank where a portion of the boat rests upon the shore with the stern to which the motor is attached lying in the shallow water adiacent the shore. Under such circumstances, using a conventional mount, the operator usually tips the motor at an angle so as to lift the propeller from the bottom of the lake or stream and leaves it in that position while he attends to other matters ashore.

When an outboard motor is tilted upon its axis and left in that position for any considerable time, gasoline or other fuel and lubricant is very likely to drip from the tanks of the outboard motor into the boat itself or in the adjacent water constituting both a fire hazard, and a water contaminating mess. This difficulty is, of course, overcome if the outboard motor under such circumstances can be raised vertically so as to maintain its normal operating attitude rather than by a tilting rotation.

One object of my invention therefore is to provide improved means for positioning the propeller of an outfit 2,713,842 Patented July 26, 1955 ice board motor at varying depths in the water for shallow or deep water operation.

Another object of my invention is to provide means for accomplishing this variable depth control of the motor by means of vertical movement of the motor rather than tilting.

Still another object of my invention is the provision of a novel, vertically movable mount for an outboard which is suited for attachment to the transom of a boat and to which a motor may be secured and which includes means for counter-balancing the weight of the motor to make the vertical reciprocation thereof easy.

Yet another object of my invention is to provide a motor mount as described above wherein the draft of the motor may be controlled by the foot of the operator.

ther objects and advantages of my invention will be apparent from the following description and drawings of which:

Fig. 1 is a vertical longitudinal section through the stern of a representative boat, illustrating the mount of my invention in section, secured to the transom of the boat and having an outboard motor mounted thereon;

Fig. 2 is a plan of the outside of the transom of the boat provided with my mount;

Fig. 3 is a section which may be considered as being taken substantially along the line 3-3 of Fig. 2 looking in the direction of the arrows;

Fig. 4 is a section which may be considered as being taken substantially along the line 44 of Fig. 2 looking in the direction of the arrows; and

Fig. 5 is a section similar to Fig. 4 showing however my mount in its elevated position.

in Fig. l is illustrated a boat 10 having a transom 12 and a conventional outboard motor 14 which is normally secured to the transom 12 by clamps 16. The motor is capable of being tilted on the clamps 16 by means of a pin connection 18.

Instead of the conventional clamps securing the motor directly to the transom 12, my invention includes a set of four tracks 29 vertically mounted on the transom 12 by more or less permanent fastening means, such as screws 22 or the like. These tracks are arranged in pairs, the pair members being opposite each other on the inside and outside of the transom and the two pairs being equally spaced to the right and to the left from the center of the transom. The tracks have longitudinal grooves 24 formed on the outward facing surfaces thereof.

Two braces 26 of generally elongated C-shape constitute the next elements of my invention. These braces have deep throats, and the internal opposite surfaces 28 are formed to be complementary with and slideable on the grooved track's 2i), having ribs 30 which move in grooves 24. Although these braces are illustrated as having a solid section, a tubular or U-shaped section would serve as well and save some weight, the only difficulty with the latter sections being the provision of the ribs 30. Extending between the braces 26 is a rack 32 which may be formed of substantial sheet metal bent into a U-shape so as to have opposite parts in the inside and outside planes of the tracks 20, so overlying the top and sides of the transom as to constitute what might be termed a false transom. The motor is secured to this rack in just the same fashion as it would be secured directly to the transom in a conventional mounting of the motor. Thus, the material which forms the rack must be strong enough to withstand the clamping of the motor to it at points spaced from the upper angled edges. The rack need not extend to the lower extremities of the braces 25. All that is essential is that the rack extend down to the point where the motor clamps would normally engage it. Of course, a further extension downward 3 serves a bracing function. The rack may be secured to the braces by bolting 34 through turned edges 36, welding, or any appropriate means.

The lower ends of the outside legs of the braces 26 have formed thereon or secured thereto brackets 33 which extend parallel to the transom and outward from the center thereof. These brackets have holes 40 in the outer ends thereof and the free lower ends 42 of springs 44 are secured therein. For adjustability, the ends 42 may be threaded as illustrated and nuts used to anchor these ends. Anchor plates 46 are screwed or bolted to the outside of the transom closely adjacent the tracks 20, these anchor plates having outstanding perforated ears 4% to receive the upper ends 50 of the springs 44. The mode of attachment here may likewise be by threaded ends 50 and nuts 52. Other means of attachment will suggest themselves. Adjustment of spring tension while desirable, is not a requisite.

It is desirable that the assembled rack and braces be amply sturdy. To this end, I provide a reinforcing rib 54 of rather substantial section which extends between the inside legs of the braces 26 and lies flat against the rack and is secured to both the braces and the rack by suitable means such as welding or bolting. This rib must, of course, be below the line of attachment of the motor.

A second bar 56 likewise extends between the inside legs of the braces 26 downward of the rib 54, this bar however being secured adjacent the outer surfaces of the braces 26. A hole 53 is formed in the center of this bar and a pivot bolt 6i) extends therethrough. A hearing 62 is situated in the hole 58 to encompass the bolt 60 to permit free rotation thereof.

A fulcrum point 64 is provided on the inside of the transom which may consist of a bolt 66 secured to the transom to protrude substantially therefrom. A lift bar 68 is mounted by a hole in its end on the bolt 66. A spacer 70', on the bolt 66, holds the end of the lift bar away from the transom for movement of the bar in a plane parallel to the tracks 20 and close to but slightly spaced from the braces 26. The end of the lift bar opposite the pivoted end may be termed the handle 72, and may be moved upward or downward, but it is emphasized that it may be so operated either by hand or foot.

in the middle of the lift bar, a longitudinally elongated hole is provided through which the pivot bolt 60 passes. By virtue of the slot 74, as the handle 72 of the lift bar 68 is raised, the pivot bolt 52 will slide therein since it is positionally fixed with respect to the bar 56. The rotary motion imposed on the bolt by virtue of its being moved within the slot 74 is accommodated by the bearing 62. deeds or nuts 76 at either end of the pivot bolt serve to retain the pivot bolt between the bar 56 and the lift arm 68.

For manufacturing convenience, the spacing between the two opposite sides of the rack may be made to fit the thickest of normally encountered transoms and the tracks may be spaced outward from the transom to fit the braces 26 by wooden or metal strips or some such technique.

From the foregoing description, the operation of my device will be readily understood. The tracks are first secured in appropriate fashion inside and outside the transom, being spaced out therefrom if necessary to the extent required by the relative thinness of the transom. The anchor plates 45 are likewise secured to the outside of the transom and the fulcrum 64 to the inside thereof. The assembled rack and braces are slid down over the tracks and the springs 44 are connected between the brackets 35; and the anchor plates 46. The motor may then be secured in conventional fashion to the rack by means of the clamps 16. The spring tension is then adjusted by the nuts on the threaded ends 42 and 50 of the springs -34, preferably so that the motor is weightless 4- when the rack is in its lowermost position on the tracks 29 or in other words, when the top of the rack meets the top of the transom. The motor is then ready to operate the boat.

in normal operating conditions the propeller of the motor will be immersed at full depth and will be situated somewhere below the level of the bottom of the boat for maximum efficiency. When, however, dangerous water is reached, the lift arm may be raised so as to pull the propeller somewhat upward to any desired degree to make operation of the motor safe. The motor, of course, will be completely protected from hazards such as rocks or snags when the propeller lies behind the transom of the boat or fully above the level of the bottom of the boat. By virtue of the mechanical advantage obtainable through the leverage of the lift arm and through the counter-balancing effect of the springs 38, the motor may be easily and quickly moved between a raised and a lowered position and is easily held in any raised position. Since the motor moves vertically there is no heavy opposition to the movement from the propulsive force of the propeller itself, as in the case of the tilting of the motor.

Of course, when the motor is not operating, as when landing, the counter-balancing efifect of springs 38, make it easy to elevate the motor out of contact with the bottom of the lake or stream, or of the shore itself. In obvious fashion, a latch may be provided of any conventional type to hold the motor in this uppermost position.

Having thus described an illustrative structure embodying my invention, but intending in no way to be limited to the structural details thereof,

I claim:

1. A mount for attaching an outboard motor to a boat, said boat having a transom and said motor having mounting clamps, comprising vertical guide means secured to said transom, means movable with respect to and guided by said guide means to which said motor may be clamped, resilient means connected between said movable means and a stationary point to counter-balance substantially the weight of said motor when said motor is at full operating draft, and means interior of said boat for continuously and variably moving manually said movable means up and down.

2. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising vertical guide means secured to said transom, means movable with respect to and guided by said guide means to which a motor may be secured, and a lever interior of said boat for moving manually said movable means up and down.

3. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising vertical guide means secured to said transom, means movable with respect to and guided by said guide means to which a motor may be secured, a spring connected at one end to said movable means and at the other end to said transom to counter-balance substantially the weight of said motor and means interior of said boat for moving manually said movable means up and down.

4. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising vertical guide means secured to said transom, means movable with respect to and guided by said guide means to which a motor may be secured, and a lift bar pivoted at one end to said transom inside said boat and connected to said movable means between its ends for moving said movable means.

5. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising vertical guide means secured to said transom, a rack overlying the top portions of the inside and the outside of the transom and having means thereon complementary to said guide means and slidable thereon, said rack being adapted to have a motor clamped thereto, and means for moving said rack up and down.

6. A mount for attaching an outboard motor to a boat.

said boat having a transom, comprising means adapted to be secured to said transom for vertical movement in the plane of said transom to which a motor may be secured, resilient means connected between said movable means and a stationary point to counter-balance substantially the Weight of the motor and means interior of said boat for moving manually said movable means up and down.

7. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising means adapted to be secured to said transom for vertical movement in the i plane of said transom to which a motor may be secured, and a lever inside said boat for moving manually said movable means up and down.

8. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising means adapted to be secured to said transom for vertical movement in the plane of said transom to which a motor may be secured, lever means pivoted at one end to said boat, a pivot interconnecting said movable means and said lever means, said pivot being rotatable with respect to one of said means and being longitudinally movable with respect to the other of said means.

9. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising a rack overlying the top portions of the inside and the outside of the transom, said rack being adapted to have a motor clamped thereto, means for securing said rack to said transom to be vertically slideable thereon in the plane of said transom and means for slideably moving said rack.

10. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising a rack overlying the top portions of the inside and the outside of the transom, said rack being adapted to have a motor clamped thereto, means for securing said rack to said transom to be vertically slidable thereon in the plane of said transom, resilient means connected between said rack and a stationary point to counterbalance substantially the weight of said motor when said motor is at full operating draft and means for slidably moving said rack.

11. A mount for attaching an outboard motor to a boat, said boat having a transom, comprising a rack overlying the top portions of the inside and the outside of the transom, said rack being adapted to have a motor clamped thereto, means for securing said rack to said transom to be vertically slidable thereon in the plane of said transom and a lift bar pivoted at one end to said transom inside said boat and connected to said rack between its ends for moving said rack.

References Cited in the file of this patent UNITED STATES PATENTS 1,894,710 Samuelson Jan. 17, 1933 2,135,907 Miller Nov. 8, 1938 2,301,903 Flader Nov. 10, 1942 FOREIGN PATENTS 607,229 France Mar. 23, 1926 907,410 France June 25, 1945 

